Extreme pressure soluble oil compositions



United States Patent EXTREME PRESSURE SOLUBLE 01L COD [POSITION S N Drawing. Application December 27, 1951,

Serial No. 263,697 I j 9 Claims. (Cl. 25233.4)

The present invention relates to improved soluble oil compositions which, when emulsified with water, form stable emulsions of high load carrying capacity.

' In the metal fabricating, cutting and related arts, use is made of emulsions which function to lubricate and cool the metal and cutting tools used in turning, drilling, grinding and similar operations. In many of such operations, the emulsions are prepared by emulsifying a suitable soluble oil with a relatively large .proportionate amount of water. The soluble oils employed usually contain as essential ingredients a lubricating base, an emulsifying agent and water and, for contemplated use in heavy duty machining operations such as the high speed cutting of hard alloy steels, the soluble oils generally contain a suitable extreme pressure agent. The ingredients used in soluble oils are generally employed in rather well defined proportionate amounts so that the soluble oil itself will be a homogeneous solution stable against ingredient separation, will readily emulsify with formation of a stable emulsion when added to and agitated with a relatively large proportionate amount of water and in such emulsified form, will possess a high load carrying capacity.

Although the 'artis aware of soluble oils that contain materials other than of petroleum origin as the lubricating base, the most widely used, to my knowledge, are soluble oils in which the lubricating base is of petroleum origin and may comprise a mineral oil that boils in the lubricating oil boiling range, a spindle oil, a pale oil or types similar thereto. Lubricating bases used for soluble oils include distillate oils derived from petroleum crudes and which may vary over a rather wide range of being distillate oils having a viscosity of about 100 SUS at 100" F. and one reason for usageof mineral oils of the lower viscosity characteristics is that, in general, theymay be rendered emulsifiable more readily than high viscosity oils.

The art is also aware of many emulsifying agents usable in soluble oils to facilitate the dispersability and emulsifiability of the lubricating base with water. illustration, emulsifying agents used for soluble oils include metal or onium base soaps of organic acids such as the alkali metal or onium base soaps of fatty acids, naphthenic acids and sulfonic acids. As examples of the organic soaps, the oleates of'alkylol amines such as the diand tri-ethanol amine oleates have been employed and, of the metal soaps, use has and is still being made of alkali metal soaps of organic acids such as the fatty acids, sulfonic acids, naphthenic acids'and the like, with r r 6 C 2,773 03 2 known to the art that impart extreme pressure properties to such compositions. Materials used include elemental sulfur, sulfur-containing materials such as sulfurized fatty oils, sulfurized ester waxes such as sulfurized sperm oil, sulfur chloride treated fatty acids, and others. Also used as extreme pressure agents are phosphorus-containing materials illustrated by the product marketed as Ortholeum 153 by E. I. du Pont de Nemours and Co., Inc., and understood to comprise tricresyl phosphate and chlorine-containing substances such as chlorinated hydrocarbons marketed as Chlorinated Hydrocarbon-70" by the Pennsylvania Salt Manufacturing Company of Philadelphia, Pa. and having a chlorine content of 67-70 percent by weight.

Additionally, numerous soluble oils, and particularly those containing a metal soap as an emulsifier, contain coupling agents adapted to facilitate dispersion of the emulsifying agent in the oil. Coupling agents used include alcohols of the aliphatic type such as the propanols and butanols, polyhydric alcohols such as the glycols and more specifically diethylene glycol, glycol 'ethers such as diethylene glycol monobutyl ether, and combinations thereof. Illustrative of such agents in combination is diethylene glycol with diethylene glycol monobutyl ether with suitable results being obtained by use in soluble oils of a combination, based on theweight ofthe soluble oil, of about 0.3 to about 3 percent of a polyhydric alcohol and an amount of the alcohol ether of from about one to about five times that of the polyhydric alcohol. a

Water, in addition to being an essential ingredient in soluble oils, must be correlated with the remaining ingredients of the composition in orderto provide a 'soluble oil that is homogeneous and stable against ingredient separation and which readily forms stable emulsionswhen added to relatively large proportionate amounts of water to form the compositions ready for usein cutting operations and the like. For example, soluble oils that contain water, but in an insutficient amount, have a tendency to. gel, whereas soluble oils that contain an excessive amount of water usually evidence instability caused by the soap separating out of solution. Thus, and with respect to a particular soluble oil composition a rather well defined range of Water will be tolerated thereby;

Addition of water to the composition in an amount in excess of that tolerated leads to formation of a cloudy or hazy appearance and oftentimes stratification occurs due to ingredient separation. Generally speaking, the

more water within, limits .whichcan be tolerated by a soluble oil in stable solution, the more stable will be the emulsion resulting fromlater addition of the soluble oil to a relatively large proportionate amount of water necessary to prepare it for use. In certain soluble oil compositions increased amounts of water can be tolerration of soluble oils having narrower ranges of water sodium and potassium soaps of such acids being more tolerance.

It is an object of the present invention to provide novel stable homogeneous soluble oil compositions that have an exceedingly wide range of water tolerance and readily form. stable emulsionsof high load carrying capacity. Another object is to provide novel stable homogeneous soluble oil compositions possessing an exceedingly wide range of water tolerance and possessing high load carrying capacity without requiring exceptionally" large Patented Dec. 4, 1956 3 amountsof extreme pressure agents. Still another ob ject is to provide stable homogeneous soluble oil .compositions that contain a. novel combination of ingredients whereby the compositions possess an exceedingly wide water tolerance, readily form stableernulsions that-possess a high load carrying'capacit'y and which, due to their high water tolerance, may be. prepared withoutneed of critical control as compared to oils of .lesser water tolerance characteristics. It is still. another object to provide such stable homogeneous soluble oilsof low soap content that possess a high water tolerance and are capable of forming emulsions that possess an exceedingly high load carrying capacity with? low concentrations of extreme pressure agents.

The present invention relates to stable, homogeneous liquid compositions adapted for-use as soluble oils that possess desired properties as aforecliscussed' and which result by use, as a lubricating base in ;the composition, ofa suitable solvent extract of petroleum origin. The lubricating base employed may consist .ofethesolvent extract per se or mixtures thereof with a mineral oil. Hence, the compositions embodied herein comprise a lubricating base, an emulsifying agent, an extreme pressure agent, water in an amount .suflicient to inhibit the composition against gelation but lessthan an amount sufiicient to induce ingredient separation, andar'e further characterized in that the; lubricating base contains a solvent extract of petroleum origin. 7

Mineral oil solvent extraction processes are well known to those experienced in .the artand since the extraction processes per se are not .a part .of the present invention it is not deemed essential to describe such processesindetail herein. For purposes of illustration, however, such solvent extraction processes entail use of solvents such as beta, beta-di-chloroethyl ether, furfural, phenol and other suitable solvents under extraction conditioris to preferentially extract from themineral oils the aromatic-containing molecules therein. In more specific illustration, furfural is a widely used and typical extraction solvent and, for purposes of illustration, extracts from mineral oils by use of such a solvent are employed herein to describe this invention.

The improved soluble oil compositions obtained by practice of the present invention are illustrated by the data in the following tabulation (Table I) which includes compositions as embodied herein and a conventional soluble oil, in which the lubricating base component-was devoid of a solvent extract of petroleum origin, used for comparative purposes. The compositions set forth in Concentrate: Percent by weight .Soap solution 64.6 Tall oil 7 5.2 NaOH B.) 3.0 Diethylene glycol 5A5 Ethylene glycol monobutyl ether 12.7 Water 9.0

The ingredient shown as soap solution as used herein comprises about percent of the water soluble sodium salts of mahogany acids derived from petroleum, about 5 percent water, and the balance mineral oil. The ingredients are shown in formula amounts, soaps being formed'by action of the sodium hydroxide with the tall oil prior to blending with the remaining constituents.

The extract employed in preparation of the extractcontaining compositions in the tabulation was a furfural extract per se obtained from a Pennsylvania crude oil by subjecting the oil ,to distillation from which a pressable distillate was obtained, said distillate being press dewaxed and subjected to distillation to remove gas oil and yield a bottoms fraction. The bottoms fraction was then solvent extracted with furfural to yield an extract comprised predominantly of aromatic-containing molecules and having the following characteristics:

Gravity, API 7.8 Flash point F 405 Fire point F 475 Viscosity at 100 F SUS 2765 Viscosityat 210 F SUS 71.7 Carbonresidue' 0.9-1

The load carrying capacity of the compositions shown in Table I were obtained on a Falex tester in which test the loads were applied gradually while rotating the pin at a constant speed. This device, which is a wellknown lubricant testing machine, comprises a steel pin rotatable between two nonrotatable steel jaws carrying V-shaped bearing surfaces and means for clamping the rotating pin betweenthe bearing surfaces with adjustable force. In conducting the test, the oil emulsion under observation was kept in contact with the revolving pin while the. latter was clamped between the bearings with steadily increasing force applied to the jaws. The amount of force, as indicated on the load gauge of the machine, required to cause seizure between pin and bearings represents failure of the test composition.

Table ,1

om si ion (By. Wei h Load' Carrying. Capacity (Average) of Emulsion Compositwu Water (10% of composition and No; Concen- (Over and 90% water) Guago Reading Mineral Oil Extreme Pressure Agent. Extract trate abrge water in Pounds coneentrate) 59 (100 Pale) 18 (Suliurized Sperm Oil) l 23 3,500. do .g 59 23 Entire loadof Falex tester 0 10 (Sulfurized Sperm 0il) 20 Do. 12 (100 Pale) 9 (Suliurized Sperm O11) 52 18 9 Do. 12 (55 Pale) 7 do... 52 18 9 D0. 7 12 (#2 Fuel) d0 51 18' 10 Do. 13 (#2 Fuel) 5 (Chlorinated He. 70)-- y 62 20- Do. .....do 10 (Ortholeum 153")-- 57 f 20 D0.

1 Viscosity of 100 SUS at 100 F. 1 Viscosity of 55 SUS at 100 I Petroleum distillate (#2 Fuel Oil) with viscosity of 35-40808 at 100 1.

er oil conventionally used in soluble oil compositions,

Referringto Table l, composition No. 1 relates to a soluble oil containing sulfurized sperm oil as the extreme pressure agent and, as the lubricating base, a n 1 i n- Composition No. 2 .was identical to composition No. 1

except that the lubricating base was a solvent extract."-

was a clear stable homogeneous liquid composition but which, upon further addition ofwater, evidenced instability by developing a cloudy appearance. ing compositions in Table II relate to compositions as creased load carrying capacity. The marked improve embodied herein and, as shown, such compositions posment in load carrylng capacity imparted to such comsessv substantinally higher tolerances for water. Compositions by use of the solvent extract .is 'even more appositions to 13, containing the extract per se or in parent upon reference to composition No. 3 which, almixture thereof with a mineral oil as the lubricating though it contamed only 10 per cent of the extreme pres base, possessed substantially higher water tolerances as sure agent, carried the entire load of the Falex tester 10 compared to composition 9 even though compositions 10 whereas composition No- 1 (of 18% sulfurized sperm to 13 contained a lower percentage of soap and a larger content) didnot carry the load to such an extent. Comproportion of lubricating base to soap. Thus, and as position Nos. 4 to 6, inclusive, although containing only; shown by the data in Table I and Table II, the practice one-half of the extreme pressure agent content of comof the present invention enables preparation of composiposition No. 1, also carried the entire load of the Falex 15 tions of relatively high load carrying capacities and'extester. As shown, composition Nos. 4 to 6 contained, ceptionally wide tolerances for water.

Table II Composition (By Weight) Approximate Ratio of I Maximum Lubricating Composition No. Amount of Base to Mineral Oil Sulfurized Extract Ooncen- Water Concentrate Sperm Oil trate Tolerated a (in addition to water in concentrate) 58.5 (100 Pale) 17.9 22.8 0.8 2. 6:1 9. 9 68. 9 19. 7 1. 5 am 11.5 (100 Pale). 9. 0 50. 7 17.8 11.0 a. 5:1 11.5 (as Pale) 9. o 50. 7 17.8 11.0 3. 5:1 11 (#2 Fuel)... 8. 4 48.0 16.6 16.0 a. 6:1

as the lubricating base, a mixture of the solvent extract with low viscosity mineral oil fractions ranging from the mineral oil of 100 SUS at 100 F. of composition No. 4 to the No. 2 fuel oil of composition No. 6. A feature of the compositions as illustrated by Nos. 4 to 6 is that, as compared to composition 1, they not only contained a much lower concentration of extreme pressure agent but also a lower content of soap as they contained less concentrate than composition 1. Composition Nos. 7 and 8 have been included to illustrate cmbodiments of the invention using, as an extreme pressure agent, a substance other than sulfur-containing com- 7,

load carrying capacity possessed thereby shows that compositions based on a lubricating base containing the solventv extract, in accordance with this invention, may be prepared with relatively high load carrying capacityby use of agents chemically different from the sulfur-containing substance of compositions 1 to 6, inclusive.

Whereas the foregoing tabulation relates to compositions as embodied herein and the relatively high load carrying characteristics thereof, the following tabulation (Table II) illustrates compositions as embodied herein with data pertaining to water tolerance characteristics. The data shown in the tablein the column entitled Approximate Maximum Amount of Water Toleratedf re-; lates to-the'percentage by weight of water which could be incorporated in the compositions shown, over and above the amount of water in the concentrate, without substantial, if any, evidence of instability of the composition. In Table II composition No. 9 relates to a conventional soluble oil consisting of a conventional mineral oil as a lubricating base, sulfurized sperm oil as an ext-reme pressure agent, and the concentrate described hereinbefore. Such a composition tolerated a maximum of about 0.8 percent of water over and above the water in the concentrate. Composition No. 9, containing the ingredients and amounts thereof set forth in the table,

As aforedescribed, the compositions of the presentinvention comprise a lubricating base, an emulsifying agent, an extreme pressure agent, and water with the lubricating base generally being the major component, based upon the weight of the composition. When, as aforedescrib'ed, the lubricating base comprises a mixture of the extract with mineral oil, the relative proportion of extract to mineral oil in the lubricating base may be varied over a rather wide range, depending upon factors such as the ultimate viscosity desired, obtaininent of which is facilitated by blending of the viscous extract with a low viscosity mineral oil, the desired increase in water tolerance as compared to the mineral oil per se as the lubricating base, and the like. As to. the mineral oil component of the lubricating base, suitable therefor are liquid fractions obtained as petroleum distillates such' as those having a viscosity up to about 200 SUS at F. and, in some instances, even higher, but usage "of low viscosity petroleum distillates such as those in the 1. No. 2 fuel oil range (e..g. 35-40 SUS at 100 F.) low viscosity pale oils (e. g'. 55 SUS at 100 F.), and higher viscosity pale'oils (e. g. 100 SUS at 100 F.), is preferred. Although the relative amount of a mineraloil fraction to extract may be varied depending upon factors such as aforesaid, and additionally upon volatility characteristics desired for the soluble oil composition, highly suitable compositions as embodied herein comprise the extract in a major amount by weight based on the weight of the lubricating base. g

As is apparent from the illustrative compositions set;

forth hereinbefore, the amount of extremepressure agent The remain- V than' or highers thamthclconcentnationsi shown, depending;

upxoneparticular resulta'desired, astthe describedzimpr'ovee merits: resulting from; use; of the? solventf extract" in the: lubricatin'gbase may be efiected:inscompositions contain in g; extreme; pressure agent-shin; amountsaotherthan 'tho'se specificallyset: fortha hereinbetore." However; in mostcases, the amount. of extreme pressure a'gentze'mploye'cl is generally in amountsfof from about22 to about 25-. per cent by weight ofthe-composition With/referenceto the extremespressure agents, use ofsulfur-containing-.materials is; preferred althoug'ln; as: shown-'- hereinbef ore', the invention maybe satisfactorily, practiced; with use: of other: extreme; pressure -agents,;. and particularly, oil=solublechlorine-containing and phosphorus-containing extremepressure agents.-

Moreover, and due. to. the exceptionally wide range I of water tolerated by compositions as embodied herein, it is obvious that 'such compositions may be prepared that contain water in amounts that vary considerably, based 0111116 WCighTOf'thBCbmPbEitiGDI Iii' broadaspeet; H1653 fore, the amount of water present in: the" composition should be suflicienftoinhibitgelation" bufless' tlfi'n an amount-'sufiicient to induce ingredient separation. Although the amounts-of water tolerated by compositions as embodied herein dependsonfactorssuch as the amount of extract in the-lubricating base or the amount of 'soap employed, andthe-like'; it is apparent fromthe foregoing data that compositions containing relativelyihigh amounts of. water may be prepared that are stable homogeneous solutions and form stable oil-in-water.femulsions, i. eJ-tlie.

typjeof emulsion desired inf the use" of soluble oil-s fo y Y V v ingibase comprising.(a). an extract consisting essentially preparation of lubricating and coolant compositionsfinr:

metal fabricating compositions. Illustrativeofsuchcompositions is composition No. 13, which contains about 18 percent water, consisting of the waterpresent in the concentrate plus'the amount 16 percent) shown as water tolerated over and above tliat'ih' the concentrate.

mineral oilfraction, a: Water-soluble soap as an cmulsify= inga'gent, an extremepressure-agent; and"wat'er"in' an" amount-sufiicien'tto inhibitsaidcom osition-againsf elation butle'ss" than an; amount" sufficient to'indnce separa-' donofsaidcomposition. V

2;"A stablesolubleoil composition"comprising; in"

homogeneous solution, a" liibficating base-i11 major" amounhba'sed upon thew'eight' of said composition, a water soluble soap as an" emulsifying agent; a'n'extreme" pressure a-gent and'water 'in an amount s'uffic ient to in"- hibit' gelation" but'less tliana'n" amount suffi cient w induce separation-of saidcomposition; said lubricatingbase' comprising (i1 a -predominantlyaromatic 'extract obtained by 'furfural extraction of apetroleum fraction in mixture with (b) a mineral oil distillate havingaviscosity"not exceeding'about'200- SUS at 100"F. and about 44 to-45 SUS at 210 saidextract being present in an aniount snbstantiallygreater: thansthe airtounti ofi-said mineral-1 oil distillate;.- V r t 32315 composition, ass-defined. in: cla'irri. 2,,- wherein; the soap isia metal soap not an organic: acid. A stablesoluble? oil composition" comprising; in; homogeneousisolution; a lubricating base-in major amount based upon the weight-ofrthecomposition, a water soluble metal soapiof anorganic acid-as an emulsifying: agent, an extreme pressure agent from the group consisting otZ sulfur-containing; phosphoruscontaining and chlorinecontainingextreme pressure agents, and water 'in-' an: amount sufiicient to inhibit saidrcomposition against gelatiombut. less than an 5 amount sufficient to induce separation-of said composition, said lubricating-base comprising a predominantly. aromatic extract obtained by furfural extraction-of a petroleum"fractiomanda mineral=distillate fraction having a viscosity not exceeding 200 SUS at 100 F. and about 44 to 45 SUS at 210 B, said extract being present in an amount substantially greater than"theatribiiiifdf'saidinineral oil distillate fraction.

5. A stable soluble oil composition comprising, in homogeneous solution, a lubricating base in major amount based upon the weight of the composition, a water-solubleisoapz as-anemulsifying agent, an extreme "pressure agent from the group consisting of sulfur-containing, phosphorus-containing and chlorine-containing extreme pressure agents, a coupling agent in an amount sufiicient to disperse said soap in said lubricating base, andlwater *in an amount sulficient to inhibit said composition' against'ig e lationbut less than an amount sufficient tov induce separation-ofsaid composition, said lubricatof theflmorearomaticcontaining molecules extracted from a petroleum fraction with furfural which preferentially extracts the more aromatic-containing, molecules from said petroleum fraction and' (b), a miueratoil' distillate fraction -hai'vir'i'g a viscosity not exceeding about" 200 SUSat" 100 F." and about 4410 45 SUS 'at 210"" PL, thearriount' of ext'ractbeing substantially greater'than the amount of saidimmeralxoil distillate fraction.

References cited inthe fileof thispatent UNITED" STATES PATENTS 2,2231,2 14 Nelson et--al.- Feb, 11, 1941 2,291,066 .July 28, 1942,- 2,304,1-25 Dec. 8,,1942- 2,320,263.-' Carlson etial.- May; 25,4943 2,340,035 Zimmeret al. Jan. 25,1944 2,413,353. Hunten et a1.- .Dec. 31,11946 

